High-quality and thin reservoir of tight conglomerate prediction in Maxi area of Junggar Basin

The reservoir of Triassic Baikouquan Formation on Mahu slope in Junggar Basin is characterized by low porosity,low permea?bility,and thin tight conglomerate,with only the subaqueous grayish green conglomerate with medium porosity being the high?quality res?ervoir. Because central frequency of seismic data is low (25~30 Hz),the thickness of the thin layer is about 10 m,and the impedances of high?quality reservoir and tight layers are overlapped in these reservoirs,the commonly used post?stack impedance inversion and pre?stack simultaneous inversion are not very effective in prediction of high?quality and thin reservoirs.In this paper,based on core,logging and test data,the authors carried out the petrophysical analysis and established the petrophysical chart by using P?impedance and vp/vs , and then identified the parameter of the effective reservoir of this area.Finally,the authors conducted the pre?stack geo?statistic inversion that combines the advantages of the simultaneous inversion and geo?statistics inversion,and predicted the high?quality and thin conglom?erate reservoir.The result of inversion indicates that the pre?stack geo?statistics inversion can effectively identify the high?quality and thin conglomerate reservoir and provide reliable basis for further exploration and development.